The invention relates to devices for cleaning contact lenses.
As is well known, contact lenses normally require, at intervals, to spend a period immersed in a sterilising solution. Typically, the user will store the lenses in an appropriate solution overnight. There are available one-step solutions where the lenses are placed in the solution at night, preferably after cleaning, and are simply removed from the solution and inserted in the eyes in the morning.
However, a two-step method is often considered to be superior, where the lenses are placed in a sterilising solution, typically hydrogen peroxide solution, following which the lenses are immersed in a neutralising solution. Although lenses are usually immersed in the sterilising solution overnight, one advantage of the two-step method is that the sterilising step can take as little as 30 minutes, followed by the neutralisation step of 10 minutes or so. As well as the two-step method being preferred, it may also be the only method available to someone who is allergic to some extent to solutions used in the one-step method.
However, the preferred two-step method currently has the disadvantage that it is inconvenient for the user to have to remove the lenses from the sterilising solution, introduce them into a neutralising solution, and then wait while the neutralisation takes place. Often the sterilisation is carried out overnight and the neutralisation step must be carried out in the morning before the user can insert the lenses into the eyes. It is therefore fairly common for the lenses to be left for insufficient time in the neutralising solution or even, in some cases, for the neutralising step to be omitted entirely. The result of inserting an un-neutralised lens into the eye can be very painful leading to irritation which can last for many hours.
The present invention sets out to provide a contact lens cleaning device where a required sequence of immersions, such as the two-step method referred to above, can be carried out automatically, with appropriate time delays, so that the lenses have completed their treatment and are available for use when required by the user.